1. Field of the Invention
The present invention relates to a mechanical latch system such as is commonly used with a sealed container having a lid.
2. Description of the Prior Art
Latch mechanisms for containers which require a water-tight or sealed enclosure are well-known. Typically, a gasket must be compressed in order to seal off the interior of the container. Such containers are often used to protect electronics, electrical devices, and other components in harsh or corrosive environments, such as waste treatment plants, chemical facilities, and other facilities which have hazardous or reactive materials. In such environments, the latch must be durable and easy to operate as well as providing pressure against the entire gasket so that the interior of the container remains sealed.
In addition, needs for the types of latches and handles which are used with the containers vary with the application. With some applications, it is preferred to simply close the container in a latched position, while in other applications, it may be necessary to have a keyed lock or have a latch mechanism capable of being locked with a padlock. In addition, it is preferred that it is clearly marked which way the latch mechanism needs to be rotated in order to latch or unlatch the system. The latching mechanism should also provide a mechanical advantage to aid in tightly closing the seal.
Prior latch mechanisms require many interacting parts and a pair of moving latch bars which may fail. The prior latches often do not provide evenly-applied pressure to the gasket. In addition, some latches do not provide a stop to prevent movement of the latch in a latched or fully unlatched position, making it difficult for a user to determine which way to turn the latch mechanism or what position the latch is at. Prior latching systems provided for locking the lid, but included actuator members which could be easily removed with simple hand tools so that the containers were not secure from theft or vandalism.
It can be seen then that an improved latch mechanism is needed which provides easy latching and unlatching, and which provides clear direction to a user how to actuate the mechanism. Furthermore, the latch should be adaptable to a variety of latching needs providing several levels of security. It can be further appreciated that such a latch mechanism should not adversely impact the integrity of seal with the container and should provide reliable latching with a minimum of moving parts while having high durability under harsh conditions. The exposed portions of the latch must be able to withstand the harsh environments in which the latch may be used without being easily removed when the latch is locked.